Persistent pathology of the patent foramen ovale: a review of the literature

Development and Validation of an Individualized Nomogram for Predicting Patent Foramen Ovale-Associated Stroke: Patent Foramen Ovale Morphology-Based Analysis

BACKGROUND

We previously reported four patent foramen ovale (PFO) morphological types that influenced right-to-left shunt (RLS) grades. Herein, we aimed to study the relationship between PFO morphology and cryptogenic stroke (CS). We further developed a nomogram based on four PFO morphological types and functional parameters to guide clinicians in judging the risk of PFO-associated stroke.

METHODS

This was a retrospective observational study involving adult patients with PFO between January 2020 and November 2022. Patients were divided into a PFO-associated stroke group (CS group) and a group without cryptogenic stroke (non-CS group). Four types of PFO and RLS grades were analyzed. Nomograms were made to predict PFO-associated stroke using multivariable logistic regression analysis. The discrimination performance of the model was internally validated and assessed using the receiver operating characteristic.

RESULTS

We enrolled 389 patients (male, 182 patients; female, 207 patients) with PFO, the mean age was 43.3 ± 8.1 years. The derivation cohort comprised 293 patients (CS group, 186 patients; non-CS group, 107 patients). The predictive nomogram comprised PFO morphological types, interatrial septum (IAS) mobility distance, septum primum thickness, PFO channel length at rest, and contrast-transthoracic echocardiography (c-TTE) RLS grade during the Valsalva maneuver. A validation cohort was established (CS group, 61 patients; non-CS group, 35 patients). The model area under the curve (AUC) was 0.891 (95% confidence interval = 0.855-0.928) in the derivation cohort and 0.935 (95% confidence interval = 0.885-0.986) in the validation cohort. Calibration curve analysis showed that the nomogram had a C-index of 0.891 in the derivation cohort and 0.935 in the validation cohort. The decision curve analysis (DCA) indicated that the nomogram had clinical applicability.

CONCLUSIONS

Adding four PFO morphological types improved the risk stratification capability for PFO-associated stroke. The nomogram can identify high or low-risk PFO individuals and select patients who will likely benefit from interventional device closure.

PFO Leading to Concomitant Platypnea-Orthodeoxia Syndrome and Stroke

Platypnea-orthodeoxia syndrome is a rare entity seen in patients with patent foramen ovale, characterized by dyspnea and arterial desaturation in the upright position. We describe a case of a patient who presented with cryptogenic stroke, evidence of right-to-left interatrial shunting, and refractory hypoxemia necessitating closure of his patent foramen ovale.

The diagnostic value of contrast-enhanced transcranial Doppler and contrast-enhanced transthoracic echocardiography for right to left shunt in patent foramen ovale: a systematic review and meta-analysis

Purpose

To evaluate and compare the diagnostic value of contrast-enhanced transcranial Doppler (c-TCD) and contrast-enhanced transthoracic echocardiography (c-TTE) for right to left shunt (RLS) in patent foramen ovale (PFO) by meta-analysis.

Methods

The literature included in the Cochrane Library, PubMed, and Embase were searched by using "contrast-enhanced transcranial Doppler (c-TCD), contrast-enhanced transthoracic echocardiography (c-TTE), patent foramen ovale (PFO), and right to left shunt (RLS)" as the keywords from inception through April 30, 2024. The diagnostic accuracy research quality assessment tool (QUADAS-2) was used to evaluate the quality of the included literature. The combined sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and Diagnostic odds ratio (DOR) were pooled, and a comprehensive ROC curve analysis was performed. Statistical software StataSE 12.0 and Meta-Disc 1.4 were used for data analysis.

Results

A total of 8,536 articles were retrieved, and 9 articles that met all inclusion criteria were included in this meta-analysis. The meta-analysis results show that the combined sensitivity, specificity, PLR, NLR, DOR, and area under the SROC curve of c-TCD for the diagnose of PFO-RLS were 0.91 (95% CI, 0.88-0.93), 0.87 (95% CI: 0.84-0.91), 6.0 (95% CI, 2.78-12.96), 0.10 (95% CI, 0.06-0.18), 91.61 (95% CI, 26.55-316.10), and 0.9681, respectively; the corresponding values of c-TTE were 0.86 (95% CI, 0.84-0.89), 0.88 (95% CI, 0.84-0.91), 5.21 (95% CI, 2.55-10.63), 0.16 (95% CI, 0.09-0.31), 71.43 (95% CI, 22.85-223.23), and 0.9532. The ROC curve shows that c-TCD has slightly higher diagnostic value for PFO than c-TTE, but there is no significant statistical difference (Z = 0.622, p > 0.05). Deek funnel pattern showed no significant publication bias.

Conclusion

Both c-TCD and c-TTE have high diagnostic values for PFO-RLS. However, c-TCD has slightly higher sensitivity and lower specificity in diagnosing PFO-RLS compared to c-TTE.Systematic review registration: identifier [CRD42024544169].

The efficacy and safety of patent Foramen Ovale Closure for Refractory Epilepsy (PFOC-RE): a prospectively randomized control trial of an innovative surgical therapy for refractory epilepsy patients with PFO of high-grade right-to-left shunt

BACKGROUND

A significant proportion of patients with epilepsy have an unknown etiology and lack effective targeted therapeutic drugs. Patent Foramen Ovale (PFO) induces hypoxia and microembolism, leading to cerebral neurological dysfunction and increased epilepsy risk. This study aims to assess the efficacy and safety of PFO closure for relieving epileptic seizures in patients with refractory epilepsy associated with PFO.

METHODS/DESIGN

Recruitment takes place at the West China Hospital of Sichuan University, China, for an open-label, randomized controlled clinical trial. The trial will include 110 patients with refractory epilepsy and PFO. Disease diagnoses will conform to the diagnostic criteria of the International League Against Epilepsy (ILAE) for refractory epilepsy and the American Society of Echocardiography (ASE) for PFO. Refractory epilepsy and high-grade right-to-left shunt (RLS) of the PFO will be further diagnosed using 24-hour video electroencephalogram and transthoracic echocardiography with contrast injection, respectively. Eligible participants require a secondary or higher volume of RLS.

TRIAL REGISTRATION

Chinese Clinical Trial Registry (ChiCTR2200065681). Registered on November 11, 2022.

Machine learning in a real-world PFO study: analysis of data from multi-centers in China

PURPOSE

The association of patent foreman ovale (PFO) and cryptogenic stroke has been studied for years. Although device closure overall decreases the risk for recurrent stroke, treatment effects varied across different studies. In this study, we aimed to detect sub-clusters in post-closure PFO patients and identify potential predictors for adverse outcomes.

METHODS

We analyzed patients with embolic stroke of undetermined sources and PFO from 7 centers in China. Machine learning and Cox regression analysis were used.

RESULTS

Using unsupervised hierarchical clustering on principal components, two main clusters were identified and a total of 196 patients were included. The average age was 42.7 (12.37) years and 64.80% (127/196) were female. During a median follow-up of 739 days, 12 (6.9%) adverse events happened, including 6 (3.45%) recurrent stroke, 5 (2.87%) transient ischemic attack (TIA) and one death (0.6%). Compared to cluster 1 (n = 77, 39.20%), patients in cluster 2 (n = 119, 60.71%) were more likely to be male, had higher systolic and diastolic blood pressure, higher body mass index, lower high-density lipoprotein cholesterol and increased proportion of presence of atrial septal aneurysm. Using random forest survival (RFS) analysis, eight top ranking features were selected and used for prediction model construction. As a result, the RFS model outperformed the traditional Cox regression model (C-index: 0.87 vs. 0.54).

CONCLUSIONS

There were 2 main clusters in post-closure PFO patients. Traditional cardiovascular profiles remain top ranking predictors for future recurrence of stroke or TIA. However, whether maximizing the management of these factors would provide extra benefits warrants further investigations.